Membrane Potential Flashcards
Nernst Equation
Calculates the equilibrium potential for an ion at a given concentration across the membrane.
What is the driving force of diffusion for charged solutes?
Concentration difference and electrical potential difference across the membrane.
Role of Na, K, ATPase pump
Helps maintain resting membrane potential.
Facilitated diffusion
Allows for molecules to go down the concentration gradient easier, it does not require ATP
Allows for quicker transport of molecules that would not pass the membrane as easily alone.
Secondary active transport
Does not rely on ATP, it relies on the primary transport.
Which transporter is known to have high stereospecifity
Glucose transporter has high affinity to D-glucose rather than its L isomer.
At low solute concentrations, facilitated diffusion occurs ____________ than simple diffusion.
More rapid
Three types of carrier mediated transport
- Uniporter
- Symporter
- Antiporter
GLUT4 transporter
Transports D-glucose to the skeletal muscles and adipose tissue via facilitated diffusion.
Four Primary Active Transporters
Na-K-ATPase
Ca-ATPase
H-K-ATPase
H-ATPase
Na/K ATPase (pump)
Present in the basolateral cell membrane of all cells.
Pumps 3 Na out of the cell and 2K into the cell
Ca ATPase
2 calcium is pumped in for every ATP hydrolyzed
Found in muscle cells.
Tetrodotoxin
A toxin that blocks the sodium channel.
Prevents AP from occurring.
Toxin is present in Japanese puffer fish.
Similar to Lidocaine (to get patients numb)
Tetraethylamonium (TEA)
Blocks potassium channels
Prevents repolarization
Influx of Na
Will cause depolarization
Makes cell more positive
